JeepForum.com - Reply to Topic
Thread: Loss of power in overdrive. Reply to Thread
Title:
Message:

Register Now



In order to be able to post messages on the JeepForum.com forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.



Email Address:
OR

Log-in










  Additional Options
Miscellaneous Options

  Topic Review (Newest First)
06-14-2021 04:45 PM
TheBoogieman
Quote:
Originally Posted by Wheelin98TJ View Post
Jerry pointed out the 0.69 overdrive ratio.

In other words, you are only putting 69% power to the wheels when in overdrive.

You are around 130hp at the rear wheels stock and this is around 4,500 RPM. In overdrive you'll put about 90hp to the rear wheels at 4,500 RPM, but you'll never see that RPM in overdrive. 4,500 rpm is 190mph with 3.07 gears or 155mph with 3.73 gears.

Long story short, you're below 90hp at the rear wheels in overdrive.
Well that's depressing info.
06-14-2021 12:48 PM
Wheelin98TJ Jerry pointed out the 0.69 overdrive ratio.

In other words, you are only putting 69% power to the wheels when in overdrive.

You are around 130hp at the rear wheels stock and this is around 4,500 RPM. In overdrive you'll put about 90hp to the rear wheels at 4,500 RPM, but you'll never see that RPM in overdrive. 4,500 rpm is 190mph with 3.07 gears or 155mph with 3.73 gears.

Long story short, you're below 90hp at the rear wheels in overdrive.
06-14-2021 12:10 PM
rsurran My 2003 had 3.07 gears on 33 inch tires. Luckily it was a 5 speed stick. I posted similar to you when I first got it. After I got educated I never ran it in 5th gear (OD) except on rare occasions of flat level roads. Jeep did fine in 4th.
06-13-2021 04:33 PM
Jerry Bransford
Quote:
Originally Posted by dbbd1 View Post
Add to that above too, that maybe the transmission kick-down cable (I forgot the name right now) may not be adjusted correctly.
While the earlier 32RH had a TV (throttle valve) aka kickdown cable, the OP's 42RLE is fully electronic/computer controlled and has no kickdown cable.
06-13-2021 02:33 PM
dbbd1 Add to that above too, that maybe the transmission kick-down cable (I forgot the name right now) may not be adjusted correctly.
06-13-2021 02:16 PM
Jerry Bransford
Quote:
Originally Posted by TheBoogieman View Post
You might have 3.07 gears also.
X2, your TJ would be a real dog acceleration-wise with 3.07 in the axles.

You should be able to tell what your axle ratio is by looking at the steel ratio tag bolted onto the 9 o'clock position of your diff covers. This tag is indicating a 3.73 ratio inside the axle. No worries if yours says 3.08 or 3.74, the front and rear axle ratios are .01 different on all but Rubicons.
06-13-2021 02:09 PM
TheBoogieman You might have 3.07 gears also.
06-13-2021 10:38 AM
Jerry Bransford Your 42RLE's overdrive ratio reduces the engine rpms so much that it will barely accelerate in overdrive. Its OD ratio is .69 so the engine rpms are reduced to 69% of what they were in 3rd gear. To really accelerate you need to get out of Overdrive by either stepping hard on the gas or temporarily switching the Overdrive off.

Something else that will cause a lack of power is having installed larger tires which further reduces engine rpms. Bigger tires can kill performance and the only fix is to regear both axles to a lower ratio to get the engine rpms back up to where they should be.

What size tires are you running?
06-12-2021 07:34 PM
maintman40
Loss of power in overdrive.

2004 4.0
Starts and runs good. Wont gain speed in overdrive. Seems very sluggish. New air filter, spark plugs.

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

 
For the best viewing experience please update your browser to Google Chrome